Internal grinder and polisher



Aug. 6, 1946. H. H. TALBOYS INTERNAL GRINDER AND POLISHER Filed Jan. 28, 1943 7 Sheets-Sheet l Jizmwzfor enryfi Z&Zvy M M .l'ffazweys.

H. H. TALBOYS INTERNAL GRINDER AND ZPOLISHER Filed Jan. 28, 1943 7 Sheets-Sheet 2 .itorzzeysf 9 H. H. TALBOYS INTERNAL GRINDER AND POLISHER Filed Jan. 28, 19.43 7 Sheets-Sheec 4 ug 1946, H. H. TALBOYS INTERNAL GRINDER AND POLISHER Filed Jan. 28 1943 7 Sheets-Sheet 5 Aug. 6, 1946. H. H. TALBOYS INTERNAL GRINDER AND POLISHER Filed Jan. 28. 1943 7 Sheefcs-Sheet 6 Aug. 6, 1946. H. H. TALBOYS 2405457 INTERNAL GRINDER AND POLISHER Filed Jan. 28, 1943 7 Sheets-Sheet 7 ffazweys Patenten! Aug. 6, 1946 INTERNAL GRINDER AND POLISHER Henry H. Talboys, Milwaukee, Wis., ass ignor to Nordberg Manufacturing Company, Milwaukee, Wis., a corporation of Wisconsjn Application Januar) 28, 1943, Serial N0. 473,811

20 Cla-ims.

Th1s invention relates 110 an improvement; in internal grinders anal polishers anc1 polishing methods and has for one purpose the provision of an internal grinder eflective to finish cy1indrical inner surfaces.

One application of the invention is to polish the interior surface of tubes; pipes anti the like.

Another purpose i-s the provision of an improved means and method for truing up inner generally cylindrieal surfaces, smoothing the surfaces, grinding down a.ny inequalities and in eneral finishing the surfaces to form a, substantially true cylinder.

Another purpose is the provision of an improved interior grinding means including a. power plant and a grinding element 01 elements Which may be bodily conveyed as a unit axially along the member to be polished.

Another purpose is the provision cf improved means fr guiding and supporting such unit.

Another purpose of the invention is I;he profision of improved means f01 adjusting the thrust 01 the grinding means against an inner surface.

Another purpose of the invention is the provision of improved means for disposing of dust created by the grind.ing o1 finishing operation.

Another purpose i the provision of improved feeding means and feed limiting meang for such a device.

Another purpose is the provision 015 an improvad grind.ing head or element.

Another purpose is the provision of an improved means for adjusting the centrifuga] thrust of a rotary grinding element.

Other purposes will appear from time 130 time throughout the specification and claims.

My invention 1 illustrated more o1 lass diagrammatically in the accompanying drawings, wherein:

Figure 1 is a side elevation with parts in vertical section;

Figure 2 is a section on an enlarged scale along the line 2-2 of Figure 1;

Figure 3 is a, partial vertical longitudinal section on the same scale as Figure 2;

Flgure 1 is a section along the 1ine 5-4 of Figure 3;

Figure 5 is a section along the line 5-5 0 f Figure 3;

Figure 6 15 a section along the 1ine 58 of Figure 3;

Figure 7 is a partialplan view of the carrier for the motor unit;

Figure 8 15 asection along the 1ine 8-8 of Figule '7;

Figure 9 is a section along the line !9 of Figure 3;

Figure 10 is a plan view of the grinding head;

Figure 11 is a section a10ng the line II-.I Lot Figure 10;

Figure 12 is a, section along the 1ine I 2--I2 of Figure 10 Figure 13 is a sid eelevation of a grinding segment;

Figure 14 is a, plan view of a grinding segment holder;

Figure 15 is a section on an enlarged scalaalong the 1ine I5I 5 of Figure 1;

Figures 16, 17 and 18 illustrat e detail of a slight variation from the corresponding structures shown in Figures 3, 6 and- 9 respectively.

Lilie parts are indicated by 1ike charactels throughout the specification and draw-ings.

Referring to I;he drawings and initially primarily. tqFigure 1, I is any suitable supporting surface, floor or the 1ike. The structura supporh. ed on the surface includes generally the fo1lowfing elements: A generally indicates a aupport ing structure f0r the feeding means for the power anal grinder unit below described; B indicates a supporting device-for the motor and grinding unit when not in use; C indicates generally, supporting meansfor the tube or other element, the interior of which is to be grouncL finished, or polished.

Referring first to the structure indicated as -A it may be formed in a wide variety of Ways but: I illustrate a plurality. of uprights 2 connected by longitudinally extendir;g angle 3. The angles or the upright or both may be connected by transversely extended angles 4. Mounted on the transverse membem and shown in some detail in Figures 3, 4 ancl 5, arg a pair cf 10ngitudinally eXtendingangles 5the lowe r fl anges o-f which approach and are divided by a space asat 6. Slidable in the channel thus provided by the angles 3 is a.ny suitable transversely extending thrust member 1, herein shown asa hollow element of rectangular cr0ss section. II: is provid.-

' ed with a downwardly. extencled rack 8, which rides in and iS guicled longitudinally by.the aperture 6. 9indicates a transverse pin Which may be employed as a stop. If desired a plurality of apertures 9a may be provided f0r permitting adjustment of the st op if such adjustment is neoessary. The rack is driven by-any suitable pini on I0, mounted. on a shaft II, in any suita.ble bearings I2. The shaft I I maycarry a sprocket I3, about whichpasses a chain or belt I4, which in turn passes about a sprocket I5, driven by a friction drive Hi. i! is any suitable gear reducer and I8 any suitable source of power such as an electric motor.

II: will be understood tha'o the detailg do not form part of the present invention and What is necessary is sonne means for driving the pinion I9 anal thereby moving the rack 8 alternately in opposite directions. It Will be understood, 110W- ever, that Wheie a series of successive passes is made in order 130 treat an article of a given 1ength, where lt is desired to have alle passes extend through a. uniform distance at each pass, it may he advantageous to provide any suitahle automatic reversing means for reversing the drive.

at the end of the pass. Since such meansars well known they need not -be indicated in detail.

20 illustrates any suitable rolle means for holding the rack 8 down against the pinion H. 2I is a sto plate mounted acljacent; the right end of the unit A. Referring 110 the positiou of the parts shown in Figure 1, the stop plate 21 may be engaged by the pin 9 ab the end of th stroke in one direction or it may be engaged by some corresponding pin ab thaend of the opposite strok e in another direction. I illustrate, for example, the pivoted links 22 carrying a stop member 23 at their end. In the position in which the parts are shown in Figure 2, it stops the grinding element; in the pos'ition in which ii; is shown in Figure 3 the grinding elemenc is approximately inside, the work. If the links 22 are rotated into their opposise position, then the stop 23 will not be effective unti1 after the grinding element has been entirely withdrawn from the work. 'Ihe friction connection I6 permits slippage when any of the stops engage theplate 2l. This protects the motor from burning mit.

Controlled r moved by the element 7 and its rack 8, in response to the rotation of the pinion II), is the motor and grinding unit below described. The motor and grinder uniiz, when not in use, is housed in a supporting and aligning Shell 25 which forms part of che structure B indicated in Figure l. This Shell may be supported in any suitable manner on a plurality of uprights 26; It is also provided with a plurality of cut-outs or open spaces 21, which permit inspection of the motor and grinder unit and gives access to the motor and grinder when housed in the Shell 25 anal also permits inspection todetermine proper alignment between the grinder unit and the work supported on the element C. 28 are any suitable circumferential reinforcing rings. I'he shel1 is provided with a bottom piece 29, havi ng a lonsi tudinally extending slot 30. Ihe shell terminates a1: its right band end, referring to the position cf the parts shown in Figure 3, in a plane perpendicular 130 the axis of the Shell, which permits a close approach of the opposed edge of ehe work inclicated as D. 7

It will be understood that the interna1 diame ter of the shell 25 is substantially the same as the intern2l diameter of the work D and also that some means are preferably provided in connection with the W01k D for continuing the slot 30 or its equivalent. As an example, the whole device may be employed in finishing the interior of a. tubular element formed by rolling a sheei; of meta1 together so that the opposite longitudinally xtending edges of the sheet approach but do not meet. The space between the approaching edges provides an aperture aligned with and corresponding to the slot 33. It will be understood fahat the below described motor and grinding uni1; may be moved freely out of the shel1 25 and into the 4 work along the entire length of the work in response to the rotation of the pinion I0 and back through the work in the opposite direction and into the shell 25. In order to support the motor anal grinder unit du1ing this excursion, I provide a supporting frame including three longitudinaliy extending frame elements 31 32, and 33. 'Ihe three frame elements are connected by two or more circumferential ring elements 34. The longitudinal elements 3I and 32 may be fixed to the rings 34 by welding o1 otherwise. Preferably one cf thg longitudinal elements herein shown as 33 is mounten movably radially in relation to the rings 34 and yielding means are provided for thrusting it radially outward toward the inner surface of the shell 25 01 the work D. I illustrate, for example guiding pins 35 surrounded by compressed spring 36. The guiding pins are C011- nected to the element 33, for example by angles 31, and nass through fixed abutments 38 on the rings 34. Axial movement of the member 33 is prevented for exarnple by any suitable stops or bars 38, which with the angles 31 act as movement limiting means. In order to space the rings 34 axially apart, I also provide br&ces 40 located adjacent the member 33 and provide the stifiening which 33 cannot give because of its movable relationship With the rings.

Any s uitable means may beemployed for supporting the above described structure Within the inner faces of the member 25 and the work B respectively. I show for example, wheels or rollers 4 I. The member 3I is shown in Figure 3 as carrying four of these rollers. In the stru ctu'n; shown in Figures 3, 6 and 9, these bottom rollers, mounted on 3l, penetrate the slot 30 of the elements 29, anti thus prevent rotation of the frame formea by the elements 3I, 32 and 33 and the rings 34. I also illustrate rollers 4I at each end of the members 32 and 33, these rollers abutting against the inner surface of the members 25 and D. I1; will be observed as in Figure 3 that the cut-away port1ons 21 are out 0f line with the paths of these rollers.

In che form of Figures 16, 17 alld 18, the lower rollers 41a are mounted on the element 3l, laterally out of line with the sich 39 of the element 29. Thus all of-the sets of rollerg as shown in Figures 16, 17 and 18 engage the inner faoe 01t the work or of the member 25 and are not relied upon for preventing rotation of the structure. I prov1de instead a feather or key 133, mounted in any suitable manner on the member 3I, and adapted to penetrate the slot 33. This penetration preyents any rotation of the motor and its supportmg carrier and has the additional advantage of tending to scour out dust, and shavings from the slot. Ir, 1 thought to be advantageous to have the rollers directly engage ehe cylindrical inner surfaces. An accumulation of chips anal dusb in the s1ot may be disadvantageous, and may cause irregularities in grinding, unless scrapers or an air j et are employed to keep the slot c1ear. This is unnecessary in the structures of Figures 16 to 18. Ii, will also be understood thatif the work is not itself provided with a slot, Other means may be provicigd to prevent rotation of the body 0f the motor anal support, such 215 a rigid shaft centered on the motor.

Mounted within the frame thlls formed and supported by the rings 34, I illustrate any suitabl zmotor 42, one end of whioh is seaced in the right iing 34, referrlng to Figure 3 the other being engaged anal held in position by any suitab1e clamp plate 43. Any suitable means may be empbyed for cooling the.motor. For example, a supplemental fan 44 or under some circumstances, the device may be coupled into any suitable suction system. Under general circumstances, it is advantageous to employ the integral fan 44, as shown in Figure 3, operated by the same motor which rotates the grinding head structure. I illustrate for example in Figure 1, the suction duct 45 in communication with the housing 45 with a. transparent inspection window 41 and a connecting cylinder 48 approaching closely adjacent the end of the work D, er if desired, slipped over the end f the work D. Thug all dust created by the operation of'the device is withdrawn from the area of the work am]. ca.rried ofi. However, under mogt circumstances, I prefer to provide means for ca.using aid to pa.ss about the motor 42, obtaining the double result of coolin the motor and removing dust and grindings from the Working area. The tan 44 provides one method for air cooling anal dust disposal. It will be noted that the grinding head below described may also be provided with fan means as will later be seen.

Referring next to the grinding structure proper,

the motor shaft 42a is snrroundecl by a sleeve 45 keyed 0r otherwise firmly secured thereto. 49a, 49a, indicate a pair of hub disks pressed on or otherwise secured to the sleeve 49. Referring for example to Figures 10, 11 and 12, I illustrate a plurality of radial a.rms 50, four extending from each of the hub plates 49a, each set of armg supporting a. ring I. The arms 50 ma.y include fan va.nes 52; the purpose of which ha 'already been discussed. Therings 5I define between them a;

spa.ce for two or more shoes or Segment holders,

generally indicated at 53. The inward moVement opposite end of which is pivotd to a lever 69' which with its associatzed 1ever 6I forms a bellcrank lever structure Divoted at 52 to the rings- 5l. Adjustable on the lever 61 is a counterweight 63. 64 is a. spring extending from the unter end of the lever 51 to the hub latos 49a where, if desired it may be secured to a. pin 65 extending be tween the hub plates. At the forward end 0fthe shoe are lugs 66 to which a.-re pivotd a]ink 67 piVoted in turn as at 58 to therings 51. be adva.ntageous to provid'e acounterweight 59 at the forward end-of the link 81. The arrow inFigure 12 indicates thedirefli0n of rotation of theabove described heacl. indicate removable It may abrasiVe or polishing Segments which arepro Vided with channels 10a to receive flanges 58, o1 the shoe sides 57. The rear end of the shoe is open t permit the insertion of the seg'ments7 and a;ny suitable retaining plat H could be employed. It may, for example, be slipped into slots; 12 luthe flanges 58. The plate H may be locked in it inward position for example by the pin 13 members 15 a longitudinall extending grooved' piece 81 With a s10t:82 in alignment with the.cor responding members 29 and 30 0f the shell 25 as shown in Figure 9. 83 inclicates any suitable semicircular clamps which may be clamped down in any suitable manner as by bo1t 84. The structure-thus provided permits the firm locking (f the workbetween the clamps 80 anal 83 Withthe opposite edges of the work cylinder D abutting against the upwardly extended longitudinal fl9.nges 85 which extend a.long each side of the slot 82.

It will be understood tha.t this particular work detail and detail of work support is not of itself essential. For example, completed tubes may be operated upon in which means associated with the tube itself a.re employed for immobilizing the opposite edges of the bottoni slot. With some modifications, the structure ma.y be employed to polish.or finish th interiors of tubes having no break in the surface;

It will be understoool that the elements B anal C are so proportioned that wheu the work tube D is clamped in. position, it is properly aligned With the shell 25 and the motor and grinding unit moves re.dially out of the shel1 25 into the work tube D and back through the work tube D into the shell 25;

It Will be realized that whereas I ha.ve shown and described an operative device, still many changes might be made in the size, shape, arrangement anal disposition of parts without cle parting materiallyfrom thespirit of my invention und I wish, therefore, that my showing be taken as in a. large sense, illustrative o1 diagrammatic. The use anti operatioi1 of my invention are as follows:

I provlde mea.ns for a.nd a method of finishing interior cylindrical or partly cylindrical surfaces. My invention is weil adapted finish interiors of more or lass elongated cylihdrical members, such as pipes, conduits, a.nd the lik@ It ma.y be employed to finish interiors ofcylindrical tubes 01 t0 finish generally cylindrical' inner surfaces, which extend about less than 360 degrees of arc.

- It may be employed to finish interiorsof aper tures in members, the exteriors of which are square, rectangular or. in general, other than cylind'rical. In the particular exemplification of 1ny invention herein described and shown, I move a motor anti grinder unit axially along the element to be finished. During the axial movement of the unit, the motor rotates the head in such manner es to cause the abrasive segment 15 to thrust centrifugally outwardly agalnst the inner face 0f the work D. Centrifugal force is also efiective to urge the counterweight 63 generally radially outwardly and there is a balance of two f0rces. By adjusting the counterweight 63 in relation to its pivot 52, the centrifugal thrust of the abrasive segment i'll against the inner fa.ce of the workoan be adjusted. The Segments 70 and. the shoes in which they are mounted, are thrust outwa.rdiy in such fashion that centrifugal force permits them to adjust their position in relation to tl'ie inner fa.ce of the work. For example, anal referring to Figure 12, the segmentlfl and .its supporting shoe are connected by the intermediate link 57 to the rings 5I a s at 68and. the 1ink 59 provides a. loose connection Witli a center E2. Thus the subjection of the shoeand segment to centrifugal force resultg in a generally uniform thrust of all parts 0f the outer surfmes 0f the segment' against the inner surface of the work.-

It will be understood, of course, that the counterweight 53 is so manipulated that the cen trifugal thrust of the segment 70 will alwa.ys exceed the centrifugal outward thrust of the counterweight since otherwise there would be no grinding,

In the use of the device, I find that it operates not merely as a polishing or finishing device but as a truing device. For example, if there are prjections 0xunevennesses in the inner wal1 of the work, these unevennesses tend to be planed or ground down With considerable rapidity. Inert-ia prevents a, certain adaptation of the shoe I0, 130 lozal reductions in radius and thug inward projections or unevennesses tend to' be planed er ground off. Experience indicates that not merely minor irregularities or sudden projections -are taken out but tha t the interior of the work is ground down 120 a close approximation eo a tru1y uniform diameter.

It is even possible to convert a more 0r less tapered taube from a tube of uneven diameter by controlling the length of the passes anal giving the t001 a progressively gmater numbey of passes through the initially more restricted part of the tube. My invention may thus be employed 1:0 0btain the following eifects: (a) The smooth finishing of Ehe interior surface; (b) the elimination of irregularities and sharp variations in radius of the inner surfaces; (c) the genral truing up of the inner surface 150 give it, at a.ny ODE point, an approximation to truly circular cross secbion; and (d) rendering the interior of the tubular element of substantially uniform diameter from end 110 end.

A5 a specific example of a. practical operation of my device, projector tubes for torpedoeg max! be initially formed from fiat sheets cf metal, the sheets being bent so that opposite edges approach laut du not meet. Such sheets ca.n then be clamped in the supporting structurs C as shown in Figure. 15 with the opposite edges cf the sheet abutting against theflange 85. In that event, the work is clamped in p0sition by the c1amps the taube may then be completed nd provided with its own fittings, surrounding rings, reinforcements and the 1ike, I'his, cf course, may take platze remote from ohe structure shown herein. 'Ihe completed tube with it5 longitudinal track can then be dropped into the supporting structure C with its track aligned With the track 29 of the shell 25. In that event, t-he member 8I is mmoved from the supports 8II. Then the tube may hake its final treatment so far as the present method is concerned.

It will be understood that the cono-acting member or segment 10 may be formed. of any suitable substance. It may be abrasive 01 it may gonsist of or have secured thereto a. polishing element. Under smrie circumstances, it may even be desirable to Substitute a polishing pad or bufier. Any suitable sealing means may be mounted intermediate the ends of the motor carriage 1:0 control circulation of the air. It may be advantageous for example 110 insure that air blows along the key s1ot and cleans out the 100Se material resulting from the grinding.

It will be 'understood that the counterweighting of the sh0e 53 provides an automatic adjustment. As the grinding material weam away, the heavy meta1 shoe advances, further from the center of rotation, and thereby increases its centrifugal weight. Also, the cnunterweight retracts toward the center of rotation and thereby loses some of its centrifugal weight. This compensates for loss of actual weight of grinding material.

In connection with adjusting the counterweight 63 it is important both for controlling the' (Lutting pressure and for compensating for ehe horse 33. After the initial smoothing has haken p1ace,

power available; F01 example, where a, relatively smal1 motor isused in a smal1 taube, the thrust cannot be asgreat as in the event a large motor is used, or a.s in the event that the power source is locatd outside of the Bube.

It Will be also understood that where I employ the term grinding element, I wish it to be interpreted as of sufiicient breadth to cover any suitable grinding orv p'o1ishing element, polishing pa'ds or the like, and in general, any element operating in any sense abrasively against the suriace of the work.

It willalso be understood that; where in the claims, I employ the term tubular or hollow cylinder, or ho1low cylindrical element I wish the claims to be interpreted broadly enough to inc1ude elements in which the wa11 of the su'rface to be finished does not extenc); entirely about 360 degrees cf an: and in which the exterior-of the surface to be finished may -be squa1"e or recta.ngular or otherwise not cylindrical. 'Ihe terms tubular 01' cylindrical are not iIi-' tended to :be taken completely literally, as my method and appairatus are applicable to finish a Wide variety of structureg and a wide variety of surfaces, so long as the surfaces to be finished include a, substantial cylindrical area '0r a substantial area, arcuate in transverse cross section.

I'claim:

1. In a. finishing device for finishing the interior surface of a hollow gerierally cylindrica] element, a. motor means, means for supporting it Within and' upon the surface t0 be treated and for centering it Within said element, means for moving it axially along said surface, and a surface grinding element generally concentric With an driven by said motor means and includ ing a surface grinding member mountecl to move centrifugally toward the interior surface in response to its rotation -by the moto1j and means for reversing the movement of said motor means and surface grinding element When the surface grinding e1ement reaches a predetermined point within the hollow e1ement.

2 In a finishing device for finishing the interior surface of a tubular element, a. carriage adapted to penetrante the element to be finished, a. motor on seid carriage, a rotary grinding element 0n said carriage and a driving connection between the grinding means and the motor, mea.ns for propelling the carriage longitudinally a1ong the element to be finished, a centering support adapized 130 receive ehe carriage when the carriage is withdrawn from the element, and

means for supporting the element in axial alignment with said centering support.

a3. In a. finishing device for finishing the interior surface of a tubular element, a'carriage adapted to penetrate the element to be finished, a, rotary gflnding element; 0n said carriage and motor means on said carriage for rotating it meang for propelling the carriage longitudinally along and within the element to be finished a centering support adapted to receive the carriage and motor means when the cairiage is withdrawn from the element, and means for supporting the element in axia1 alignment with sa.id centerin-g support.

4. In a. finishing device for finishing the in-- terior surface of a, tubular element, a carriage adapted to penetrate the element to be finished a. rotary grinding element on said. carriage and means for rotating i-t, means for propelling the carriage longitudinally along the elemen1; to be finished, a centering support adapted 10 receive the carriage when the carriage is withdrawn from the element, an d means for supporting the element in axial aligmnent With seid centering support, and means for preventing rotation ef sa.id carriage in relation 130 said element and said centering support.

5. In a finishing dev-ice for finishing the in terior surface of a tubu1ar element, a carriage adapted 110 penetrate the e1ement to be finished, arotary grinding element; on said carriage and meang for rotating it, means for propel-ling the carriage longitudinally a;1ong the element 190 be finished a centering support adapt ed to receive the carr-iage when the carriag-e is withdrawn frem the element, and means; for supporting the element in -axial alignment With said centering support and mean for preventing rotation f said carriage in relation to said element anal saic1 centering support includin-g a, member projecting radially from said. carriage, said centering sup port and the e1ement 1:0 be finished being longitudinally slotted to receive said member.

6. In a finishing device f01 finishing the interior surface of tubular elements a, carriage including a, plurality of longitudinaliy spaeeo'l rings, a, plurality 0f l(mgitudinal ly extending frame elements connecting said rings means an seid frame elementg for contacting the surface 120 be fin-ished and means for moving said frame elements, with the surface contacting means thereon, into expanded position with the contacting means cdncacting the inner sxirface 130 be treated, and a rotary head mounted on said carriage, and means for rotating it.

7. In a finishing device for finishing the interior snrface o1 tubular elements, a carriage including a plurality cf longitudinally spaced rings, a plurality of longitudinally extending frame elementg connecting sa1d rings, means on seid frame elements for contacting the surface 130 be finished. and means for moving sa.id frame elements, with the surface contacting mea.ns thereon, into expanded position with the comt'acting means contacting the inner surface 110 be treated including guiding meang f0r one of said frame elements and yielding means tending normally 150 urge 117 outwardly in relation said rings, and a rotary head mounted on said carriage, and meang for rotating it.

8. In a finishing device for finishing the interior surface of tubular elements, a carriage including a plurality of longitudinally spa.ced rings, a plurality of longitudinally extending fram elements connecting said. rings, means an said frame elements for contacting the surface so be finished and means for moving said. frame elements, with the surface contact means thereon ini;o expandecl position with the contacting means contacting the inner surface to b treated, and a rotary head mounted on said carriage, and means f0r mtating 113 including a motor mounted. 011 and moving wii-h seid carriage.

9. In a finishing device fr finishing the interior surfaces of tuoular elements, a. carriage adapted 120 penetrante ehe tubular element 120 be finished, a rotary head mounted on said carriage and means for rotating it, and means for moving said carriage longitudinally'along and within the tubular element including a rack extending longitudinally from said carriage, a, pinion in mesh With said rack and means for rotating seid pinion.

10. In a finish-ing device for finishing the in- -terior surfaces of tubular elements, a. carriage adapted to penetrante the tubular element to be finishecl, a rotary head mounted 0n said carriage and means for rotating it anal means for moving sadd earriage longitudinally a1ong anal within he tubular element including a rack extending 10ngitudinally from seid carriage, a pinion in mesh With said rack and means for rotating said pinion a.nd driving means fr saic1 pinion including a, frictional connection. 11. In a finiShing device for fir1ishing the interier Surfaces cf tubula.r elements, a carriage adapted to penetrate the tubular element to be finished, a rotary head mounted on said carriage .and means for rotating i-t, gmd means for moving said carriage 1ongitudina1ly along and Within the tubnlar element including a rack extending longitudinally from saic1 carxiage, a pinion in mesh with said rack and means for rotating said pinion, and limit means. associated with said rack anal adapted terminate th excursion cf the carriage.

12. In a finishing device for finishing the interior surfaces cf tubular elements, a carriage adapt'ed to penetrate the tubu1ar element to be finished, a, rotary head mounted 0n said carri&ge and means for rotating it, ano1 means for moving said carriage longitudinally along and Within the ti1bular element includihg a rack exbendirlg longitudinally from said Carriage, a. =pinion in mesh with said rack and means for rotating said pinion, and adjustable 1imit means aSsociated with said rack and adapted to termina.te the excursion of the carriage.

13. In a finishing device for finishing the interior surfaces of tubular elements, a. carriage adpted to penetrate the tubular element to be fini shed, a rotary he'a'd mounted on said carriage and. means f0r rotating it, and means for moving seid carriage longitudinally along and within the tubu1ar element including a rack extending longitudinally 'from said carriage a, pinion in mesh with said rack and means Tor rotating seid pinion, and means for changing the direction of drive 01 the pinion when the carriage reaches a predetermined point in its movement along a tubular element.

14. In a v finirshing device for finishing the interior surfaces of tubular elements, a carriage adapted penetrante the tubular element to be finished, a motor on said carriage, a rotary head on said carriage, a driving connection between said rotary head anal said motor and means for causihg a fiow of air about said motor and across the area of contact between seid. rotary head anti the work including fan means driven by said motor.

15. In a finishing device for finishing the in" terior surface 0f longitudinally s1otted tubular elements, a carriage adapted 110 penetrate the element to be finished, a rotar grinding element in said carriage, anc1 means for rotating it, means for propelling the carriage longitudinally along the element 110 be finished, a centering support adapted to receive the carriage when the carriage is withdrawn from the element, means for supporting the element in axial alignment with said centering support, and means for preventing rotation of seid carriage in relation to saic1 element and said centering support, including key means projecting generally radially from saic1 carriage and penetrating said s1ot.

16. In a. finishing device for finishing the interior surfac'es of tubular elements, a carriage dapted to penetrate th tubular element to be finished a rotary head on said carriage and mea.ns for rotating it, mea.ns fr moving said carriage into, along, and out of a. tubular element, and means for securing said. tubular element in alignment With the path of movement of said eatriage, means for supporting said carriage in alignment with said tubular element, and adjacent the end f the tubul ay element, when the carriage has Ideen remove'd froni the tubu1a}r element, and. means for preventing rottion of the carriage, effectiire when the carriage is in ehe tubular element and when it is on seid exterior supporting means.

17. In a finishing deVice for finishing the interior surfaces 0f tubular elements, a carriage adapted to penetrate the tubular element to be finished, a supporting means for supporting said carriage adjacent an ena ofthe tub ular element and in alignment With the interior of said element, centering and supporting elements on seid carriage for engaging the inner face of the tubular element, the exterior supporting means for the carriage including Walls in general alignment with the tubular element and adapted to receive said centering and supporting elements on the carriage and to permit ready movement cf the carriage into and out of the tubular element, and means, effective when the carriage is n said supporting means and when it is in the tubular element, for preventing rotation of the carriage.

18. In a finishing device for finishing the interior surfaces of tubular elements, a. ca.rriage adapted to penetrate the tubular element t0 be finished, a supporting means for supporting said carriage adjacent an end of the tubular element a.nd in alignment with the' interior cf said element, centering and supporting elements on said carriage for engaging the inner f ace of th tubular 12 element, the exterior suppdrtihg' fiiearix fr fih carriage inclucling Walls in ge'riz'aial alignment with the tubular element and 'dpt6d 130 receive seid centering and supporting (alemrits o'h the carriage and to permit movemezit f the rfialge into and out of the tubular elemerit, 0119 or mdre cf said centering elements being positidm'ad penetrate longitudinally xtending slots in said supporting means and in the tubular elemqnt,

and being adapted, in cooperation therewith,to prevent rotation of the carriage.

19. In a finishing device for finishing the interior gurface of a tubular element, a carriage adapted to penetrate the element to be finished', centering and supporting connections bet w een the carriage and the opposed inner surface's of the element, constituting the sole suppbrting means for the carriage during its p'en'etratipn Within the element, meansfor preventing rotation of the carriage, a rotary finishing h'ead oh sa.id crriage, a. motor supported on said carriage, adapted to rotate said finishing head, and means' for propelling the carriage longitudinally alon and within the tubular element.

20. In a. finishing device im finishing th interior surface of a. tubular element, a. c9.rriage adapted to penetrate the element po be finished, centering and supporting connections between the carriag and the opDosed inner surfaces of the element, constituting the so1e supporting means for the carriage during its penetration within the element, means for preventing rotation cf -the ca.rriage, a rotary finishing head on saiidcai*riage a motor supported on said carriage, adapted to rofsa.te seid finishing head, and means for propelling the carriage longitudinally along am! within th tubular elemein.

HENRY H. TALBOYS. 

